Breaking the Mold
In this math activity, students conduct a strength test using modeling clay, creating their own stress vs. strain graphs, which they compare to typical steel and concrete graphs. They learn the difference between brittle and ductile materials and how understanding the strength of materials, especially steel and concrete, is important for engineers who design bridges and structures.
Testing the compressive strength of clay.
Engineers want to know the properties of materials in advance of using them in a project so they can design the structure to be strong enough to stay safe (not fail) under its anticipated forces and stresses. Thus, strength of materials is a significant area in engineering design because engineers want to be able to make informed decisions about construction materials. Many engineering companies have a team dedicated to researching and selecting the optimal materials for their products and projects to make sure their designs work dependably and last a long time.
After this activity, students should be able to:
- Define several engineering terms such as stress, strain and elasticity.
- Use calculations to determine the material properties of clay.
- Construct and analyze graphs to compare properties of different building materials used in engineering.